Zinc-selenium interaction regulates leaf photosynthesis and mediates grain sugar metabolism to improve the yield and quality of hybrid rice: A physiological perspective.

As a fundamental food crop on a global scale, rice necessitates continual focus on improving both its yield and quality. This study investigates the regulatory effects of zinc and selenium, two beneficial elements, on rice quality and yield formation, with a particular emphasis on their impact on photosynthetic physiology throughout the rice growth cycle. The findings indicate that the interaction between zinc and selenium enhances the net photosynthetic rate of rice leaves, primarily by modulating stomatal movement. Additionally, key photosynthetic parameters-such as Fv/Fm, Fv'/Fm', qP, Y(II), ETR, photosynthetic pigment content, and RuBPcase activity-show significant increases, while levels of NPQ and MDA decrease markedly. Furthermore, the interaction enhances the activities of invertase and sucrose synthetase in rice grains, thereby increasing the contents of starch, soluble sugars, and total sugars in the grains. Importantly, the synergy of zinc and selenium significantly enhances rice yield, biological yield, processing quality, appearance quality, nutritional quality, and taste quality. These results highlight the potential of the zinc-selenium interaction to enhance photosynthetic efficiency, boost grain sugar metabolism, and ultimately improve rice yield and quality. Notably, the combination of 7.5 mg/L selenium and 2 mg/L zinc yields the most pronounced effect on overall yield, while the combination of 5 mg/L selenium and 2 mg/L zinc shows the most significant impact on quality. This study suggests that harnessing the interaction between zinc and selenium offers a promising strategy for optimizing rice production, particularly in the cultivation of high-quality rice with enhanced yield and nutritional attributes.